1. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 Ch. 16 Vocabulary – Our Solar System (p. 509, 15 terms + 9)

2. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 1. Nebula A large cloud of gas and dust in interstellar space; a region in space where stars are born.

3. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 2. Solar Nebula A rotating cloud of gas and dust from which the sun and planets formed.

4. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 3. Astronomical Unit The average distance between the Earth and the sun; approximately 150 million kilometers (symbol, AU).

5. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 4. Terrestrial Planet One of the highly dense planets nearest to the sun; Mercury, Venus, Mars, and Earth.

6. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 5. Prograde Rotation The counterclockwise spin of a planet or moon as seen from above the planet ’ s North Pole; rotation in the same direction as the sun ’ s rotation.

7. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 6. Retrograde Rotation The clockwise spin of a planet or moon as seen from above the planet ’ s North Pole.

8. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 7. Gas Giant A planet that has a deep, massive atmosphere, such as Jupiter, Saturn, Uranus, or Neptune.

9. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 8. Satellite A natural or artificial body that revolves around a planet.

10. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 9. Phase The change in the sunlit area of one celestial body as seen from another celestial body.

11. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 10. Eclipse An event in which the shadow of one celestial body falls on another.

12. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 11. Comet A small body of ice, rock, and cosmic dust that follows an elliptical orbit around the sun and that gives off gas and dust in the form of a tail as it passes close to the sun.

13. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 12. Asteroid A small, rocky, object that orbits the sun; most asteroids are located in a band between the orbits of Mars and Jupiter.

14. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 13. Meteoroid A relatively small, rocky body that travels through space.

15. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 14. Meteor A bright streak of light that results when a meteoroid burns up in Earth ’ s atmosphere.

16. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 15. Meteorite A meteoroid that reaches Earth ’ s surface without burning up completely.

17. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 16. Nuclear Fusion When hydrogen combines to form helium and energy is released.

18. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 17. Proton A subatomic particle that has a positive charge and that is located in the nucleus of an atom; the number of protons in the nucleus is the atomic number, which determines the identity of an element.

19. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 18. Inner Solar System Contains the four planets that are located closest to the sun.

20. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 19. Outer Solar System Contains the five planets that are located farthest from the sun.

21. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 20. Period of Rotation The amount of time that an object takes to rotate once.

22. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 21. Revolution The motion of a body orbiting another body in space.

23. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 22. Period of Revolution The time that an object takes to revolve around the sun once.

24. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 23. Solar Eclipse When the moon comes between Earth and the sun and the shadow of the moon falls on part of Earth.

25. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 24. Lunar Eclipse When Earth comes between the sun and the moon and the shadow of Earth falls on the moon.

26. Unit 7 (Ch. 16) – Earth in the Solar System Bach 04/08/10 Grading Scale (1 point per term) A = 24 - 20 B = 19 - 18 C = 17 - 16 D = 15 - 14 F = 13 or less *2 E.C. pt.s possible